#    This file is part of EAP.
#
#    EAP is free software: you can redistribute it and/or modify
#    it under the terms of the GNU Lesser General Public License as
#    published by the Free Software Foundation, either version 3 of
#    the License, or (at your option) any later version.
#
#    EAP is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
#    GNU Lesser General Public License for more details.
#
#    You should have received a copy of the GNU Lesser General Public
#    License along with EAP. If not, see <http://www.gnu.org/licenses/>.

import random
import operator
import csv
import itertools

import numpy

from deap import algorithms
from deap import base
from deap import creator
from deap import tools
from deap import gp

# Read the spam list features and put it in a list of lists.
# The dataset is from http://archive.ics.uci.edu/ml/datasets/Spambase
# This example is a copy of the OpenBEAGLE example :
# http://beagle.gel.ulaval.ca/refmanual/beagle/html/d2/dbe/group__Spambase.html
with open("spambase.csv") as spambase:
    spamReader = csv.reader(spambase)
    spam = list(list(float(elem) for elem in row) for row in spamReader)

# defined a new primitive set for strongly typed GP
pset = gp.PrimitiveSetTyped("MAIN", itertools.repeat(float, 57), bool, "IN")

# boolean operators
pset.addPrimitive(operator.and_, [bool, bool], bool)
pset.addPrimitive(operator.or_, [bool, bool], bool)
pset.addPrimitive(operator.not_, [bool], bool)

# floating point operators
# Define a safe division function
def safeDiv(left, right):
    try: return left / right
    except ZeroDivisionError: return 0

pset.addPrimitive(operator.add, [float,float], float)
pset.addPrimitive(operator.sub, [float,float], float)
pset.addPrimitive(operator.mul, [float,float], float)
pset.addPrimitive(safeDiv, [float,float], float)

# logic operators
# Define a new if-then-else function
def if_then_else(input, output1, output2):
    if input: return output1
    else: return output2

pset.addPrimitive(operator.lt, [float, float], bool)
pset.addPrimitive(operator.eq, [float, float], bool)
pset.addPrimitive(if_then_else, [bool, float, float], float)

# terminals
pset.addEphemeralConstant("rand100", lambda: random.random() * 100, float)
pset.addTerminal(False, bool)
pset.addTerminal(True, bool)

creator.create("FitnessMax", base.Fitness, weights=(1.0,))
creator.create("Individual", gp.PrimitiveTree, fitness=creator.FitnessMax)

toolbox = base.Toolbox()
toolbox.register("expr", gp.genHalfAndHalf, pset=pset, min_=1, max_=2)
toolbox.register("individual", tools.initIterate, creator.Individual, toolbox.expr)
toolbox.register("population", tools.initRepeat, list, toolbox.individual)
toolbox.register("compile", gp.compile, pset=pset)

def evalSpambase(individual):
    # Transform the tree expression in a callable function
    func = toolbox.compile(expr=individual)
    # Randomly sample 400 mails in the spam database
    spam_samp = random.sample(spam, 400)
    # Evaluate the sum of correctly identified mail as spam
    result = sum(bool(func(*mail[:57])) is bool(mail[57]) for mail in spam_samp)
    return result,
    
toolbox.register("evaluate", evalSpambase)
toolbox.register("select", tools.selTournament, tournsize=3)
toolbox.register("mate", gp.cxOnePoint)
toolbox.register("expr_mut", gp.genFull, min_=0, max_=2)
toolbox.register("mutate", gp.mutUniform, expr=toolbox.expr_mut, pset=pset)

def main():
    random.seed(10)
    pop = toolbox.population(n=100)
    hof = tools.HallOfFame(1)
    stats = tools.Statistics(lambda ind: ind.fitness.values)
    stats.register("avg", numpy.mean)
    stats.register("std", numpy.std)
    stats.register("min", numpy.min)
    stats.register("max", numpy.max)
    
    algorithms.eaSimple(pop, toolbox, 0.5, 0.2, 40, stats, halloffame=hof)

    return pop, stats, hof

if __name__ == "__main__":
    main()
